I. Field of the Invention
The present invention relates to a system and method for producing methane gas and carbon products from carbonaceous feedstock.
II. Discussion of the Background Art
Techniques for partial pyrolysis of feedstocks as well as complete pyrolysis and gasification are known. Furthermore, high-temperature and low-temperature pyrolysis processes are known, and it is known in the art that these different processes work best with different feedstocks and give different resultants. However, obtaining consistency in the pyrolysis products has long been a problem. Prior systems have attempted to pass a gasification agent through a fluidized bed of solid; however, this requires a highly granular and reactive fuel for gasification, and as such is limited in its application. Other systems for pyrolysis pass a gasification agent through a solid bed of fuel, which requires a non-caking fuel with high mechanical strength. Likewise, high and low temperature pyrolysis processes are each better suited to pyrolizing different feedstocks, limiting the range of feedstocks that prior art pyrolysis systems could process. As such, there is a need in the art for pyrolysis systems that can accept a wide variety of fuels.
Furthermore, though both high-temperature and low-temperature pyrolysis processes produce combustible, high-BTU materials, these resultant combustibles are often lower grade and they often contain harmful impurities, such as heavy metals, which can contaminate the environment when these materials are combusted. As such, there remains a need in the art for a method of purifying the resultant products and sequestering obnoxious materials in order to prevent them from entering into the environment.
Furthermore, though the acceptable input organic or synthetic materials for pyrolysis have ranged widely in the past, there remains a need for pyrolysis systems that can process municipal solid waste in order to eliminate landfills, waste organic and synthetic material, and animal waste. There also remains a need for clean, efficient systems for gasification of coal to globally reduce the dependence on oil drilled and pumped from the Earth's crust.